Not very good support at DIVX although at the bottom of DIVX's page DivX Support FAQs | DivX.com
in fine print they say.....
**These require a third party direct show filter be installed
.avi or .divx (with MPEG-4, DivX 3-6, XVID, MJPEG and MP3, AC3**, DV)
.mpeg, .mpg (with MPEG-1, MPEG-2* and MP2, AC3**)
.ts, .tp, .m2ts, .mts (with MPEG-2*, H.264 and AC3**)
.rmvb, .rm (with Real Video 10 and Real Audio 10)**
.vob (with MPEG-2*, H.264 and AC3**, LPCM)